Not long ago I posted what I think is the solution to what you propose. The Rudder is not powered, it deflects, and in doing so removes energy from the system; it has no impetus to hold anything but centered, more energy outside the system, meaning stability, not chaos. The airstream wants to bully the panel, not the reverse. There can be no "helicoptering", like a pine seed spinning slowly down in the forest, the "tips" are way out of mass, drag, and inertia to maintain that image. In fact, they are so incongruent, what I am getting with my second iteration is a slick plummet, no chaos, no "low speed". The higher I go before dropping it, the faster it drops. I'm working on getting some video, that will take time, but my sis is a CG professor, and maybe I can have a chat with her. I'd need help posting the images anyway.
Done for the day I am. All the best mm43